cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 

Quick tip on Manual Focus and STM Lenses

DanSF
Contributor

I saw this video of a quick tip on STM lenses and focusing.  This issue must confuse lots of people, and even the presenter says "Review this before contacting support" so I thought I'd share here.

 

The author states "When manually focusing with STM lenses, an electronically powered manual focus system turns on, which may cause users to think something may be wrong with the camera when there isn't. Find out which steps you have to take before you start photographing."

 

http://learn.usa.canon.com/resources/videos/tutorials/quick_tips/qt_manualfocus_stm.shtml

 

I'm glad I saw that since I now have some STM lenses and I thought that going into MF mode & turning the focus ring is all that is necessary. Not quite true, as the camera can't be sleeping.

3 REPLIES 3

zimou13
Apprentice

Canon introduced STM autofocus lenses primarily to resolve an issue that their previous Ultrasonic motors could not: smooth autofocus when shooting video. In still photography, focus occurs before the image is shot, so that how the motor gets to focus is not as big a concern. But in video, focus (well specifically autofocus) occurs while video is being recorded, therefore, the relatively jerky focus from Ultrasonic motors was not preferred. There is more to it than that of course, but thats the short answer. If you are not shooting video, there is no specific reason to favor STM lenses over non-STM lenses, other than most are very new. Tutuapp 9Apps Aptoide


@zimou13 wrote:

Canon introduced STM autofocus lenses primarily to resolve an issue that their previous Ultrasonic motors could not: smooth autofocus when shooting video. In still photography, focus occurs before the image is shot, so that how the motor gets to focus is not as big a concern. But in video, focus (well specifically autofocus) occurs while video is being recorded, therefore, the relatively jerky focus from Ultrasonic motors was not preferred. There is more to it than that of course, but thats the short answer. If you are not shooting video, there is no specific reason to favor STM lenses over non-STM lenses, other than most are very new.


And a bit quieter. Sometimes that matters; sometimes it doesn't.

Bob
Philadelphia, Pennsylvania USA


@zimou13 wrote:

Canon introduced STM autofocus lenses primarily to resolve an issue that their previous Ultrasonic motors could not: smooth autofocus when shooting video. In still photography, focus occurs before the image is shot, so that how the motor gets to focus is not as big a concern. But in video, focus (well specifically autofocus) occurs while video is being recorded, therefore, the relatively jerky focus from Ultrasonic motors was not preferred. There is more to it than that of course, but thats the short answer. If you are not shooting video, there is no specific reason to favor STM lenses over non-STM lenses, other than most are very new.


Ditto for adjusting the aperture, which is far more noisier than focusing.  Way more.  When you use a DSLR, you do not hear the lens “stopping down” because the mirror slap drowns out the clicks.

--------------------------------------------------------
"The right mouse button is your friend."
Announcements
01/18/2023: New firmware version 1.1.1 is available for EOS R6 Mark II
01/09/2023: Help ensure your autofocus is properly aligned with a Canon Precision Alignment
01/03/2023: Welcome to CES 2023!
12/08/2022: New firmware version 1.0.5.1 is available for EOS C70
12/07/2022: New firmware version 1.7.0 is available for EOS R5
12/07/2022: New firmware version 1.7.0 is available for EOS R6
11/22/2022: New firmware available for EOS R3, EOS R7 and EOS R10
11/16/2022: We're thrilled to be ranked among the Best Employers for Veterans in 2022 by Forbes.
08/31/2022: New firmware version 1.1.1 is available for RF 70-200mm L IS USM
08/09/2022: New firmware version 1.2.0 is available for CR-N 300
08/09/2022: New firmware version 1.2.0 is available for CR-N 500
07/14/2022: New firmware version 1.0.1 is available for CR-X300
06/10/2022: Service Notice:UPDATE: Canon Inkjet Printer continuous reboot loop or powering down
06/07/2022: New firmware version 1.3.2 is available for PowerShot G7 X Mark III
05/31/2022: Did someone SAY Badges?
05/26/2022: New firmware version 1.0.5.1 is available for EOS-C500 Mark II
05/26/2022: New firmware version 1.0.3.1 is available for EOS-C300 Mark III
05/10/2022: Keep your Canon gear in optimal condition with a Canon Maintenance Service
05/05/2022: We are excited to announce that we have refreshed the ranking scale within the community!
04/26/2022: New firmware version 1.0.1.1 is available for EOS R5 C
03/23/2022: New firmware version 1.0.3.1 is available for EOS-C70
02/09/2022: Share Your Photos is back!
02/07/2022: New firmware version 1.6.1 is available for EOS-1DX Mark III
01/19/2022: READY FOR ANYTHING EOS-R5 C
01/13/2022: Community Update. We will be retiring the legacy profile avatars on 01/20/2022. Click this link to read more.